From 2e7c47e2eb3cfeadf78a1ccbac8492c60d508f23 Mon Sep 17 00:00:00 2001 From: Duoming Zhou Date: Fri, 5 Dec 2025 11:48:31 +0800 Subject: [PATCH] usb: phy: fsl-usb: Fix use-after-free in delayed work during device removal commit 41ca62e3e21e48c2903b3b45e232cf4f2ff7434f upstream. The delayed work item otg_event is initialized in fsl_otg_conf() and scheduled under two conditions: 1. When a host controller binds to the OTG controller. 2. When the USB ID pin state changes (cable insertion/removal). A race condition occurs when the device is removed via fsl_otg_remove(): the fsl_otg instance may be freed while the delayed work is still pending or executing. This leads to use-after-free when the work function fsl_otg_event() accesses the already freed memory. The problematic scenario: (detach thread) | (delayed work) fsl_otg_remove() | kfree(fsl_otg_dev) //FREE| fsl_otg_event() | og = container_of(...) //USE | og-> //USE Fix this by calling disable_delayed_work_sync() in fsl_otg_remove() before deallocating the fsl_otg structure. This ensures the delayed work is properly canceled and completes execution prior to memory deallocation. This bug was identified through static analysis. Fixes: 0807c500a1a6 ("USB: add Freescale USB OTG Transceiver driver") Cc: stable Signed-off-by: Duoming Zhou Link: https://patch.msgid.link/20251205034831.12846-1-duoming@zju.edu.cn Signed-off-by: Greg Kroah-Hartman --- drivers/usb/phy/phy-fsl-usb.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/usb/phy/phy-fsl-usb.c b/drivers/usb/phy/phy-fsl-usb.c index 40ac68e52cee7..e266a47c4d483 100644 --- a/drivers/usb/phy/phy-fsl-usb.c +++ b/drivers/usb/phy/phy-fsl-usb.c @@ -988,6 +988,7 @@ static void fsl_otg_remove(struct platform_device *pdev) { struct fsl_usb2_platform_data *pdata = dev_get_platdata(&pdev->dev); + disable_delayed_work_sync(&fsl_otg_dev->otg_event); usb_remove_phy(&fsl_otg_dev->phy); free_irq(fsl_otg_dev->irq, fsl_otg_dev); -- 2.47.3